from The Century Dictionary and Cyclopedia
- n. A name common to plants of the genus Xanthium: also applied to the bedstraw, Galium Aparine, and in Jamaica to Triumfetta. See bur-bark.
Sorry, no etymologies found.
It is a variety of the American cocklebur, often called sea-burdock, or the  hedgehog-burweed, a stout and common weed of the western states.